Loading coil case



May 11, 1937. J RANGES 2,079,697

LOADING com CASE Filed May 15, 1935 2 Shets-Sheet 1 FIG? lNi/ENTOR V J. E. RANGES A TTORNEV May 11, 1937. J. E. RANGES 2,079,697

LOADING COIL CASE Filed May'15, 1935 2 Sheets-Sheet '2 FIG. 4

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v 4 5 11 I I 4 /4 2 l5 /4 o o 5 1 4 /2 4a 4 23'" 4 a O O l2 4 I so 32 a INVENTOR J. E. RANGES ATTORNEY Patented May 11, 1937 PATENT OFFICE LOADING COIL CASE John E. Ranges; East Rutherford, N. J., assignor to Bell Telephone Laboratories, Incorporated, New York, N. Y., a corporation of New York Application May 15, 1935, Serial No. 21,593

8 Claims.

The present invention relates to inductive devices and more particularly to an assembly of loading coils and the connecting means for the wiring thereto and to protecting means therefor.

It is anpbject of this invention to provide loading coilsfor communication cables that will be reliable and relatively inexpensive.

It is a further object of this present invention to provide supporting and housing means for the small and less ponderous loading equipment recently developed from the use of new alloys for loading cores.

A feature of the present invention involves mounting means relatively small in size to pass through a center hole in a small loading coil or a series of small loading coils to carry the coils and their connections in arigid reliable manner. A further feature of this invention involves a -woodenstructure capable of centrally supportingthe' loading coils and their. terminals and wiring. e

Qther features of the invention include the combination of spaced heads for a double walled metallic casing from which the electrical equip- "ment' is insulated'and by which structure the electrical equipment is shielded from inductive interference.

Other objects and features of this invention will be seen in the drawings accompanying this specification of an illustrative embodiment of the invention in which:

Fig. 1 is a perspective view of loading coil mounting means according to this invention;

Fig. 2 is a partial cross-section of the assembly of Fig. 1 in a case;

Fig. 3 is a perspective of a modification for special coils; and

Fig. 4 is a partial section of the assembly of Fig. 3 in a case.

The loading coils are of the kind used for loading telephone lines or cables of small size connecting to stations at considerable distance from a central switching point.

In Fig. 1, a lead shleathed telephone stub cable 9 carries a loading coil assembly arranged along and supported by the outer lead covering of the cable. The individual loading coils 10 are spaced from one another by wooden blocks l2 spaced along the lead sheath. Each individual coil rests on one of two paper washers I4 which are arranged on both side faces of a metallic washer l5 employed for inductive shielding in the customary manner. The lowest metal washer I5 is retained on the lead sheath by a securing means, such as a wiped or soldered joint I'l. String wrappings l8 secure the individual local cables or leads I9 in a group below the joint I1, suitable strap members 23, preferably of insulating material, longitudinally space the wooden blocks I 2 from one another in desired relationships and furnish a support for the lead wires in the local cables l9 connecting to the terminals 24 mounted or pegged on each wooden block.

A circular head plate 25 arranged to be the outer closure for the loading coil case is secured to the lead sheath on the stub cable in a wiped or soldered joint 26'. The head 25 is spaced by a felt washer 21 from a metal inner head 28, the felt washer being arranged to prevent solder from a joint 30 around the periphery of the head closure from entering the loading coil chamber and possibly short-circuiting lead wires. The outer casing enclosing the loading coil assembly consists of a lead sleeve 3| closed at the bottom by a metal plate 32, such as a brass plate. This lead sleeve is stifiened by an internally arranged steel sleeve 33 disclosed and claimed in a patent application Ser. No. 20,959; filed May 11,1935 by Greenidge. A paper lining 34 insulates the interior of the easing and its loading coil assembly from the inner metal sleeve 33.

An embodiment shown in Figs. 3 and 4 provides for satisfactory mounting means on a central dowel of loading coils of various sizes even to the smallest so far proposed. The stub cable 39 passes through the head closure of a loading coil casing similar to that in the embodiment of Fig. 1, being secured thereto in similar manner. The stub cable 39, however, terminates just inside the head and the leads or local cables 40 extend downwardly through the casing around both sides of the loading coil assembly. The loading coil assembly is hung from a metal bracket 4| resting on the upper edge of the steel reinforcing inner casing 33 at its extremities. A bolt 43 passes centrally through the loading coil construction placing a tension on the assembly of loading coils through the bracket 41, a nut 4 44 and lock washers 45. Hollow wooden spools 48 and 49 of suitable sizes and of length respectively equal to the thickness of an adjacent coil telescope over the central metal dowel and space the Washers l4 and I5 and the wooden blocks l2 the proper distances from one another for the particular loading coils employed. The loading coils 50 and 5| are shown as of unlike dimensions because of differing requirements of loading characteristics. This proposed arrangement for supporting loading coils accommodates itself very Well to variations in coil dimensions. Each coil 50 is carried on one of the spools 48 and relative to the coils on the terminals to which:

they connect.

What is claimed is:

1. A loading -coil casing having a cylindrical casing means, a head recessed within the case and secured thereto in a metallic joint as by solder, a rigid metal head supported from within the casing and spaced from the outer head closure, and a fibrous washer arranged between the two heads to prevent molten solder from entering the casing.

2. In a loading coil structure, a casing, a stub cable entering the casing and terminating just within the casing, a bracket member retained at its extremities within the casing, local cable from the stub cable passing around the bracket member, a long bolt passing approximately centrally through the bracket member, loading coils spaced along the bolt, and connections from the local cable to the loading coils.

3. In a loading coil structure, a casing, a stub cable entering the casing, a bracket member securing a loading coil assembly to the side walls of the casing, a long bolt secured to the bracket member, loading coils spaced along the bolt, hollow spool members each of suitable size to locate an individual coil member centrally on the bolt arranged within each loading coil and connections from the loading coils to the stub cable.

on' the bolt, loading coils mounted between the spacing members, spool members each of suitable size strung in place on the bolt members, to center the individual coils on the bolt and local cable providing connection between the stub cable and the loading coils.

5. A loading coil structure in a casing, a stub cable entering the casing and terminating just within the casing, a rigid loading coil assembly secured only to the side walls of the casing, a long bolt extending centrally of the loading coil assembly, insulating spacing members strung on the bolt, loading coils mounted between the spacing members and terminal connections for the loading coils on the insulating spacing members.

the insulating block members and coils"into ja, unitary structure, and bolt means toYhold the assembled structure rigidly under pressure, cit erted through the blocks disposed centrally of each coil.

7. A loading coil assembly comprising a l ng; bolt, a series of loading coilsfarran'ged onthe bolt, blocks strung on the bolt and arranged transversely between adjacent coils, a hollow spool within each coil for approximately centering the coil on the bolt and for protecting the,

coils from undue pressure in tightening of, 'the bolt, and stripinsulatiori parallel to thebolt to carry local cable connections to the coils.

tallic joint as by solder, a rigid metalhead supported within the casing-andspaced from the outer head, a tight soldered joint between ,the head and casing and a fibrous washer clamped,

between the two heads toseal the interior'fof the casing from molten solderemployedin seat ing the outer head to the main casing JoHN an was;

5 8. A loading coil casing, i a head recessed within the casing and secured thereto in ame- 

